New Mercedes Raises Question: What's The Right Amount Of Driving Automation Now?

Autos
A lifetime in the car business, first engineering, now communicating

2018 Mercedes-Benz S560 4MaticSam Abuelsamid

Technological innovation is nothing new to the brand with the three-pointed star. Ever since Karl Benz drove his Patent Motorwagen for the first time more than 130 years ago, Mercedes-Benz has been a technological pioneer. Along with pioneering engine technologies like diesel and direct injection, active safety has been at the heart of the brand. From the debut of the first electronic anti-lock brakes in 1978, the Mercedes-Benz S-class has consistently been the launch platform for these technologies and the 2018 edition takes another step closer to automated driving. After a week in the refreshed S560, I have to ask, is this a step in the right direction?

As a young engineer, we often joked about how over-engineered many German cars seemed to be and the S-class has always seemed to fit this description. Truthfully, over-engineered is not actually the right term here. The S-class is and always has been a rolling proving ground for new technologies. In the active safety arena, in addition to the aforementioned ABS, it brought us traction control, electronic stability control, adaptive cruise control and many other features that are now commonplace on mainstream cars.

Baby steps toward the automated future

Like the AMG E43 I drove earlier this year, the S560 features radar sensors and a stereo-vision camera system looking down the road. In the S560, the driver assist systems also utilize the map data as a long range sensor in a manner similar to what Cadillac Super Cruise does but it goes even further in its capabilities. From these sensors you get the usual adaptive cruise control that maintains a safe distance to the car ahead, automatic emergency braking, lane keeping assistance, etc.

The dual cameras in front of the mirror watch for road markings and speed limit signs. My time in the S560 brought more challenging autumn weather than the summer weather when I drove the E43. Along with bright sunny skies, I also spent time in driving rain. When it comes to detecting lane markings, the Autoliv-supplied stereo-camera system has proven to be far more consistent in detecting where the road is than any of the monovision Mobileye systems I’ve used.

It virtually always saw where the lane markings were with one distinct exception. After about 20 minutes of driving in heavy rain, a familiar warning about a dirty sensor popped up in the instrument cluster and the system disengaged. The alert didn’t indicate which sensor needed cleaning, the cameras or radar, but given the rain, I opted not to get out and clean it, but I took over full control instead. About 10 minutes later the system indicated that it was ready again so the rain must have rinsed off whatever was obscuring the sensor view. This is a very fundamental problem that engineers are going to have to resolve before highly automated vehicles can be widely deployed.

When the system was able to operate with unobstructed sensors, the lane keeping assist generally did a decent job of tracking the center of the lane, at least in a straight line. Through curves, the S560 never wandered out of the lane, but it didn’t feel quite as sure-footed as the Cadillac. I think the Cadillac’s use of the cameras on the side to help locate the lane markings makes its tracking a bit more stable than what Mercedes has been able to achieve with just the forward facing cameras. The Cadillac for now also has the exclusive on hands-off operation.

2018 Mercedes-Benz S560 4MaticSam Abuelsamid

While I give Cadillac the edge on lane tracking, Mercedes does provide several capabilities the American sedan does not. Like the E43, the S560 can change lanes automatically when the driver taps the turn signal. The side radars for the blindspot monitor detect if there is a gap in traffic and then the steering wheel gently edges the car over into the lane indicated by the turn signal. As with tracking through curves, the Mercedes does feel like it’s overshooting slightly, as it seems to go slightly past the lane center before correcting back. The system doesn’t jerk the car around, but neither does it feel quite as confident as an experienced driver. The control just needs a bit more refinement. Perhaps, the Mercedes engineers need to follow Cadillac’s lead and utilize the side cameras for a bit more information.

Both the Cadillac and Mercedes use the map data to look down the road and automatically adjust the cruise control set speed where needed when approaching a curve, resuming the driver requested speed on exit. However, because the big German isn’t geofenced to highways like the Cadillac, can use this look-ahead capability anywhere. If Intelligent Drive is engaged around town, tapping the turn signal stalk will cause the system to look at the map and automatically slow the car down as you approach the next corner where a turn can be made.

Driving along a main thoroughfare at the posted 45 mph limit, I tapped the right turn signal half a block prior to an intersection. At the right time, the car smoothly slowed itself down to 20 mph so I could steer around the corner and then just as smoothly resumed the the prior speed, all without ever touching the brake pedal. It was almost magical. Similarly when driving along a road with a series of three roundabouts for entry and exit ramps to a highway, the S560 slowed for each and then resumed its previous speed after I navigated around.

2018 Mercedes-Benz S560 4MaticSam Abuelsamid

As an engineer and a technology geek, I found all of this really cool and impressive. However, also as an engineer, I found it a bit troubling, with the whole system kind of falling into the uncanny valley of automation. The cameras can read speed limit signs and automatically reset the target speed for the cruise control. However, they don’t read other traffic indicators like stop and yield signs or lights. Thus you still have to use the brake for those situations.

The reality is while Intelligent Drive is capable of a doing a number of important driving tasks, it cannot handle others that are even more important so you really shouldn’t be using it around town. GM acknowledges the limitations of Super Cruise in its current incarnation and has incorporated safeguards to try to prevent inappropriate use. Mercedes-Benz can do things Cadillac can’t, but still requires hands on the wheel and allows the system to be engaged in places where it probably shouldn’t. Tesla’s original AutoPilot had similar capabilities before they dropped Mobileye but it was less consistent. The Mercedes at least never tried to follow an off-ramp that I hadn’t manually steered onto. By most accounts, AutoPilot 2 still hasn’t come close to catching up to the original. Other systems from BMW and Volvo lack the consistency of the Mercedes and Cadillac systems.

2018 Mercedes-Benz S560 4MaticSam Abuelsamid

So which is better? To be honest, I can’t really say. Each has pros and cons that don’t overlap and within their respective operating domains, they do a lot right and do it better than competitors. But they also miss out on enough capabilities that I can’t honestly say that I’d recommend either one to an average consumer. They each reduce driver workload to a degree that may be enough to trigger some overconfidence in their capabilities. Frankly I think a step back to more limited adaptive cruise control and lane departure warning may be a better choice until we’re truly ready to release a highly automated system that requires no driver engagement.

For decades now, the big Mercedes-Benz sedan has been a technology leader, the launch pad for most of the active safety devices that are now common to almost all new cars. We’re still several years away from anyone being purchase a truly automated car for use on public roads. Most of the self-driving cars that average people will have access to will be through automated ride hailing services but the affluent will certainly be able acquire cars like this one that can take complete control while they climb into that executive seat to work or relax.

The problem for Mercedes-Benz and their competitors is that between now and then, such a hype bubble has been inflated over automated driving that they need to be seen as progressing toward that goal. The more I experience incremental steps like Intelligent Driving, Super Cruise and Pilot Assist, the more troubled I become that perhaps we are pushing the current technology farther than is appropriate when a human must remain involved. These systems truly are in the uncanny valley where they are automated enough that an average driver is likely to develop a level of trust that probably isn’t justified. That opens the potential for more accidents or people deciding that the technology can’t be trusted and opting not to buy next time. The industry needs to take extreme care with its next steps.

I’ve spent my entire adult life working in and around the automotive industry. After earning a mechanical engineering degree from GMI I spent the next 17 years working on electronic control systems that help cars stop, go and change direction before I drove away to write abo...